As cards to be used in financial institutions and other facilities for the purpose of realization of cashless service and personal authentication, conventionally there is a magnetic card in which a magnetic stripe is formed on a plastic substrate surface, and an IC card in which an integrated-circuit chip (IC chip) is embedded in a plastic substrate and an IC terminal is placed on a plastic substrate surface. Then, reading and reproducing information from/to these magnetic card and IC card is carried out by a card reader equipped with a magnetic head and/or an IC contact.
The card reader reads magnetic information saved in the magnetic card and writes new magnetic information into the magnetic card through making the magnetic head come into contact with, and slide on the magnetic stripe on the magnetic card surface. Also, the card reader reads electronic information saved in the IC card and writes new electronic information into the IC card through making the IC contact come into contact with the metal terminal (IC terminal) on the IC card surface.
On this occasion, if the IC card is pulled out intentionally or accidentally in the course of reading/writing electronic information, the IC communication gets interrupted. Techniques to avoid such interruption are as described below (Refer to Patent Documents 1 through 3).
In the case of a magnetic card reader disclosed in Patent Document 1; as soon as an IC card is inserted, magnetic detection is carried out by a magnetic head. If no magnetism is detected, it is judged that the card is an IC card and then the card is locked. In the case of IC card processing devices disclosed in Patent Document 2 and Patent Document 3, it is detected by using a metal sensor such as a hole element whether an IC card has been inserted or not (The metal sensor responds to a metallic IC terminal). When an IC card is inserted, the card is locked. When a card having no IC terminal (such as a card having only a magnetic stripe) is inserted, the card is not locked.    Patent Document 1: Japanese Unexamined Patent Application Publication No. H02-126386    Patent Document 2: Japanese Unexamined Patent Application Publication No. H02-126385    Patent Document 3: Japanese Unexamined Patent Application Publication No. 2005-70870